| 摘要 |
The compounds of formula I, in which R<1> is H, alkyl, aralkyl or diaralkyl, R<2> is H or a halogen and R<3> is H, alkyl, aralkyl, aryl, aryloxy, benzoyl or 2-thienocarbonyl, R<2> and R<3> not being simultaneously H, are obtained by halogenation of a ketone of formula II, followed by dehydrohalogenation of the intermediate halogenated derivative of formula III by means of a strong base. The compounds of formula I are useful as intermediates for the preparation of pharmaceutically active compounds. <IMAGE> |
